1. Field of the Invention
This invention relates to parts constituting a vibration system of a speaker.
The present application claims priority from Japanese Application No. 2005-240151, the disclosure of which is incorporated herein by reference.
2. Description of the Related Art
FIG. 1 is a side sectional view illustrating a structure of a conventional double-cone speaker.
The conventional double-cone speaker is equipped with two diaphragms, a main cone 1 and a sub-cone 2, which are vibrating parts.
The main cone 1 is attached such that an edge damper 1B is formed integrally with the outer periphery of the main cone 1, and is secured to a speaker frame 3. The inner periphery of the main cone 1 is coupled to the outer peripheral face of a voice coil bobbin 5 which is vibrated in its axis direction by being driven by a magnetic circuit 4. The sub-cone 2 is placed inside the main cone 1 and mechanically connected to the leading end of the voice coil bobbin 5.
FIG. 1 also shows a damper 6 which is interposed between the speaker frame 3 and the voice coil bobbin 5. The damper 6 supports the voice coil bobbin 5 in such a manner as to permit it to vibrate in the axis direction.
A conventional speaker structured as described above is disclosed in JP-A-2000-125392, for example.
The main cone 1 and the sub-cone 2 which are vibrating parts for use in the double-cone speaker are typically formed of a thin resin film such as a polypropylene film, a polyimide film, a polyphenylene sulfide film or an aramid film.
In the manufacturing process of the speaker, the vibrating parts, such as the main cones 1 and the sub-cones 2, are individually nested inside one another as shown in FIG. 2 (in which the sub-cones 2 nested inside one another is illustrated), and then transferred to the assembling process of the speakers.
In the assembling process of the double-cone speakers, the nested main cones 1 need be removed one by one, and the nested sub-cones 2 need be removed one by one every time the sub-cone 2 is attached to a speaker.
At this point, however, because the main cones 1 and the sub-cones 2 are formed of a thin resin film or the like as described above, the nested main cones 1, or the nested sub-cones 2, are in close contact with each other. This gives rise to situations in which the nested cones may be not easily removed one by one, some cones may be removed together at a time or when the cones are removed one by one, the cone may be damaged. As a result, a reduction in the efficiency of assembling speakers is caused.